feat: add bot restart functionality via API and Discord command

tests/test_api_surface.py

@@ -11,6 +11,7 @@ from zyrarbot.settings import Settings
 EXPECTED_ENDPOINTS = {
     ("get", "/api/status"),
     ("get", "/api/health"),
+    ("post", "/api/restart"),
     ("post", "/api/play"),
     ("post", "/api/play_file"),
     ("post", "/api/pause"),
@@ -71,6 +72,19 @@ class ApiSurfaceTest(unittest.TestCase):
         self.assertTrue(self.spec["openapi"].startswith("3."))
         self.assertIn("ŻyrarBOT", self.spec["info"]["title"])
 
+    def test_restart_endpoint_calls_restart_state(self):
+        import asyncio
+        from unittest.mock import MagicMock
+        from zyrarbot.ui.api.routers.status_router import restart_bot
+
+        mock_request = MagicMock()
+        mock_restart = MagicMock()
+        mock_request.app.state.restart = mock_restart
+
+        result = asyncio.run(restart_bot(mock_request))
+        self.assertEqual(result, {"status": "restarting"})
+        mock_restart.assert_called_once()
+
 
 if __name__ == "__main__":
     unittest.main()